Apple is trying to make it harder for developers to abuse users' information collected through apps. According to a report from Bloomberg, Apple updated its App Store Review Guidelines last week with more detailed rules on what developers can do with users' Contacts address book information. Now, developers cannot make databases using address book information collected from iPhone users, nor can they share or sell such databases to third parties.

"Do not use information from Contacts, Photos, or other APIs that access user data to build a contact database for your own use or for sale/distribution to third parties, and don’t collect information about which other apps are installed on a user’s device for the purposes of analytics or advertising/marketing," states the updated guidelines. Those found in violation of the new rules could be banned from the App Store.

Users must already opt in to sharing Contacts information with app developers, but now Apple has placed more restrictions on what developers can do with that information after they obtain it. Once permission is given, though, users can't pull back data funneled to a developer. However, there are controls in an iPhone's settings to revoke permission for a particular app to access Contacts information so the developers can't get any additional information from your address book.